There are known tube lamps which are bilaterally mounted by inserting them transversely to their longitudinal axes into respective sockets. For assembling or disassembling such lamps, there is no special space necessary in front of the end faces of the sockets so that the lamp casing can be provided adjacent to the outer sides of the sockets.
In recent years, however, unilaterally mounted fluorescent lamps have been increasingly used which have a base plugged into the socket in axial direction of the lamp. Consequently, a clearance is required in axial direction behind the lamps for allowing the insertion or removal of such a lamp into or from the socket. A further disadvantage of such connections is that the socket is not entirely visible when inserting the lamp thus rendering the insertion rather difficult.
It has thus been proposed to use swingable sockets which are provided with a socket body of insulating material accommodating the electrical connections and having a base portion releasably connected to a holder in such a manner that the socket body is swingable about a swivel axis. The socket body and the base portion are two separate plastic parts, whereby the base portion is a U-shaped bracket whose web is connected to the socket holder by two screws while its shanks includes boreholes for journals arranged on the socket body. Such a connection is disadvantageous as it is still necessary to screw the bracket-like base portion to the socket holder.